Salicylaldehyde complexes

The crystal structure of a dimethylgallium salicylaldehyde complex shows it to be dimeric. There is a central Ga202 ring the Ga atoms are five-coordinate with distorted trigonal bipyramidal geometry.579... 

The coordination geometry about the thorium atom in the salicylaldehyde complex, Th(OC6H4CHO)4, is dodecahedral 76 the compound is isostructural with U(OC6H4CHO)4. 

Salicyladehyde complexes. — In addition to the salicylate complexes Weissman 630 also prepared a salicyladehyde (CaH OHJCHO) complex of Eu3+ and studied the fluorescence properties of this complex. Weissman s preparation was represented as a fm-salicyladehyde complex but no chemical analysis was given in support of this composition. Recently Charles [415] has prepared the salicylaldehyde complexes of La, Ce, Pr, Nd, Sm and Eu in excellent yields by the interaction of Na-... 

The effect of the charge may also be seen in some nickel(n) complexes. The neutral complex 4.7, containing two anionic ligands obtained by the deprotonation of the salicylaldehyde derivative, is completely stabilised towards hydrolysis. In contrast, the monocationic complex 4.8, containing two neutral 1,10-phenanthroline ligands, is rapidly hydrolysed to the corresponding salicylaldehyde complex (Fig. 4-25). Presumably, the overall positive charge of the complex promotes the attack of the nucleophile upon the electrophilic carbon centre. 

The complexes [Cu(salen)]2NH SCNand [Cu(salen)]LiSCN,THF have been reported. The reaction of Cu(salen) with NO in organic solvents in the presence of air gives [Cu 5,5 -(N02)2-salen ] in almost quantitative yield. Polarographic studies have been carried out on copper(ii) complexes of NN -ethylene-bis(acetylacetoniminate) and -bis(salicylaldehydeiminate) in DMF solution. " The reaction of the bis-salicylaldehyde complex of copper(ii) with H2N(CH2)2N—CH2(i H2 or H2N(CH2)3 —CH2(iH2 yields the complexes (188) however, the reaction of Cu(OAc), with salicylaldehyde and H2N(CH2),-... 

New and more selective homogeneous catalysts continue to be developed. Very few catalysts for the homogeneous reduction of aromatic compounds are known but this year two have been reported. The first is the readily prepared rhodium complex [Rh(r -C5Me5)Cl2]2 which will reduce benzene (50°C/50atm) in the presence of a base to cyclohexane " with this catalyst a high stereospecificity for all ci5-addition is observed. The other report" concerns the use of salicylaldehyde complexes of copper and nickel for the catalytic reduction of aromatic rings, but there is some doubt as to whether the active catalysts are homogeneous or not. 

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